ARMA-DUH! Rikers Island has a ghost legion of armor and boats that sits rotting on its grounds.

When life gives you dog poo, make turd-ilizer!

Some Manhattan doo-doo-gooders are launching the city’s first-ever dog-waste composting project, hoping once and for all to stop stinky land mines from clogging tree beds and streets.

“This is a call to action,” said Saleen Shah, program director with the Citizens Committee for New York City, the nonprofit behind the big stink. “Dog poop is everywhere. It gets into tree beds and kills trees.”

NYC is home to about 2 million dogs, which produce 275,000 tons of poop per year, according to Citizens Committee estimates. That’s 275 pounds per pooch!

“It’s one of those annoying things that people think can’t be controlled,” said Citizens CEO Peter Kostmayer, “but we can solve it.”

The nonprofit will dole out grants for 10 crap-compost stations at parks and dog runs across the city.

The winning neighborhood groups will get $1,000 for a garbage bin, compostable bags and other materials to turn poop into plants.

But beware: This guano is for lawns, not vegetable gardens or anything edible.

Kostmayer said the dung pit would reduce the volume of recycled droppings by 50 percent, saving cash and space in landfills.